SECONDARY BATTERY REMAINING LIFE DIAGNOSIS METHOD, REMAINING LIFE DIAGNOSIS DEVICE, AND BATTERY SYSTEM PROVIDED WITH SAME

摘要

A secondary battery remaining life diagnosis method in which the parameters of a secondary battery in an initial state are stored in memory and after a prescribed period of time has passed, the remaining life for the discharge capacity and direct current resistance of the secondary battery is calculated on the basis of the initial state parameters stored in memory, a discharge characteristic at a first current value, and a discharge characteristic at a second current value larger than the first current value. In the prediction of the remaining life of a secondary battery, this method makes it possible to calculate the remaining life for a discharge capacity maintenance rate, direct current resistance growth rate, and output maintenance rate, which are indicators used to determine the remaining life of a secondary battery, on the basis of discharge characteristics for two different discharge currents or charging characteristics for two different charging currents.